Study On Wear Performance Of Rotary Cutters For Thermal Spray Hard Coating

The short working life,low reliability,and poor adaptability of the rotary blades of the rotary seeding device of the rapeseed sowing device have become the bottleneck restricting and promotion.It is urgently needed to explore the application of new materials and new techniques in high rice bran and high containment.Increase the abrasion resistance,reliability and performance of rotary-growing and trench-removing parts under heavy water conditions.Low-stress scratch-type abrasive wear is the main form of damage and failure of soil working components such as rotary ploughing tools.Almost all of them are gradually developed from the surface to cause damage and destruction,and are mainly affected by the relative hardness of the abrasive and the workpiece and the composition of the soil.As an important surface technology for surface engineering,thermal spraying technology can produce wear-resistant and corrosion-resistant coatings on the surface of soil working components such as rotary hoe,prolong the service life of soil working components,and achieve energy conservation and consumption reduction.In this paper,Meike LF-HVOF supersonic flame spraying system is applied on the surface of 45 steel and rotary knife to spray WC-Ni hard coating with a thickness of about 300?m.Microhardness tester,X-ray diffractometer and field emission scanning electron microscope are used.The hardness,phase structure and surface topography of the hard coating were characterized respectively.The 65Mn spring steel was used as the comparison material.The wet abrasive rubber wheel wear test was used to simulate the abrasive wear performance of the rotary coating hard coating under the soil environment.The main conclusions are as follows:?1?Hardness test results showed that the hardness of the WC–Ni hard coating was4520HV0.3 and the thickness was 300?m.The phase structure of the tungsten carbide hard particles was WC phase.With a small amount of WC_1–X–X phase,the binder phase nickel is a face-centered cubic Ni phase,the tungsten carbide hard particle size is 2¹0?m,uniform and dense,the porosity is 8%;the hard coating thickness is applied on the surface of the rotary knife Uniform and dense,consistent with the quality and performance of 45 steel surface spray coating.?2?In the wet sand rubber wheel wear test,when the ratio of sand to water is reduced from 3:1 to 3:2,the load is increased from 40N to 110N,the WC–12Ni hard coating has a wear loss in the range of 53⁸0 mg.Fluctuation,WC–10Ni mill loss weight is 35⁷6mg;WC–Ni hard coating wear is due to binder wear caused by local hard particle peel and hard particles of micro-wear.?3?Compared with the 65Mn spring steel used for rotary knife,the weight loss of WC–Ni hard coating wear decreases by at least 14 times,which indicates that the supersonic flame spraying WC–Ni hard coating has more excellent wear resistance.Extend the life of soil working components such as rotary tillers.